基于无人机研究长三角化工园区颗粒物垂直廓线

Vertical profiles of particulate matter in a chemical industrial park of Yangtze River Delta studied by a sensor on an unmanned aerial vehicle

化工园区的颗粒物污染非常严重,但目前对化工园区的颗粒物垂直廓线研究甚少,导致无法科学地评估化工园区的颗粒物排放对周边地区的影响.在2020年8月—2021年3月期间于杭州湾上虞经济技术开发区开展了23d,共计151次的颗粒物(PM_(1.0)、PM_(2.5)、PM_(10))垂直观测实验.利用无人机搭载微型检测仪研究化工园区0—500 m高度内颗粒物在不同季节及一天中的不同时间点(9、11、13、15、17时)的分布特征.结果表明,颗粒物平均浓度大小为冬季>秋季>春季>夏季,且秋冬季颗粒物浓度远大于春夏季,最高可达152.00μg·m^(−3).由相关性分析可知,颗粒物分别与大气温度和相对湿度呈正相关,与风速呈负相关关系.颗粒物浓度总体随高度的升高而降低,由于粒径和质量影响,下降速率呈现为PM_(10)>PM_(2.5)>PM_(1.0).由粒径分析可知,在颗粒物浓度最高的当天,颗粒物数浓度主要由0.38—0.54μm细粒子组成.由日变化可知,颗粒物浓度一般在9时达到最高,在13时达到最低.

The particle pollutions in chemical parks are quite serious,but there is little research on vertical profile of particulate matters(PM)in chemical parks recently,which makes it impossible to scientifically evaluate the impact of PM emissions from chemical parks on surrounding areas.From August 2020 to March 2021,a total of 151 vertical flights to observe of the vertical profiles of particulate matter(PM_(1.0),PM_(2.5),PM_(10))had been conducted in Shangyu Economic and Technological Development Zone of Hangzhou Bay during 23 d.The seasonal and diurnal variations of PM vertical profile in the range of 0—500 m height were studied by a micro-detector on an UAV.The seasonal concentration of PM is the highest in winter followed by autumn,spring,and summer,respectively.The PM concentrations in autumn and winter with peak value of 152.00μg·m^(−3) were much higher than those in spring and summer.Correlation analysis shows that PM concentration is positively correlated with atmospheric temperature and relative humidity,and negatively correlated with wind speed.PM concentration generally was found to decrease with the increase of height in this study with their rates highest in PM_(10) followed by PM_(2.5),PM_(1.0) in order is due to particulate size and mass.Particle size analysis showed that the PM with their diameters in the range of 0.38—0.54μm are the dominant on the day with the highest PM concentration.In the diurnal variation,the PM concentration generally reached its peaks at 9 o'clock and the lowest at 13 o'clock.